Electric heater.



BEST AVAILABLE com Y PATENTED APB.. 4,' 1905. L. P. BROWN & F. J. HOLMES. I

ELECTRIC HEATER.

' APPLIOATIOH FILED 00T. 17,1904.

2 SHEETS-HEEFT 1.

BEST AVAILABLE com Hoff/'86,542 l PATENTBD APR.4,1905. l

L. P. BROWN L F. J, HOLMES. BLEGTRIG HEATER.

APPLICATION FILED OU'l. 17, 1904. 2 SHEETS-SHEET 2.

g5-juf Figure 1 is a longitudinal section of the complete device. Fig; 2 is a side view of the 'To all whom it may concernl- BEST AVAlLABLE COF.

UNITED STAQTES i Patented Alprl 4, 1905.

A PnfrENr @Fisica -LOUIS cr'. BROWN AND FRANK J, HOLMES, 'or CHICAGO, ILLiNoIs.

ELETnlc HEATER.'

'SPECIFICATION forming para o'f Letters raten N0.7ee,542, dated April 45, 1905..

Application im lomini 17.1904. s iii no. 228.828.

Beit known that we, LOUIS P. BRowN and :FRANK J.A HOLMES, citizens of the United States, residing inthe city of Chicago, county of Cook, and State of Illinois, have 'invented'- 'a newand useful Improvement in'Electric Heaters, of' which' the following is a specifica- 5 tion.

,Ounnvention relates to improvements in heatlng devlces 1n which heat is generated by.'

` electricity; and thegeneral objects of the invention are, iirst, to providea heater which shall be strong, substantial, durable, and con-' venient touse; second, to supply the heat efiiciently at the desired portion of the device; third, to provide a construction whereby the parts maybe readily as semblcd-and be easily accessible, and, fourth,V toprotect the parts from mechanicaldamage and-also Vfrom the corrosive effects of fumes and of the air, especially when the parte are. hot.` In obtaining these general objects a number o vspecitic details of Vconstruction and arrangement are employed, which will; hereinafter be more fully set forthl?l Certainofthe features of our inl' vention are applicable, broadly, to electrical heaters ingeneral, andthe accompanying claims, unless "specifically restricted, are intended ,to be broadly construed. Certain of the features,v however', are particularly adaptled tosolderingtools, `and for this reason a soldering-tool is shown, andthe generalfeatures 'aire illustrated i'n connection therewith. Wel attain ou-r-obJectsby the mechanism Illustrated Yin the accompanying'drawings, in

. l innerltube, showing the heating-'coil thereon.

3, Fig. 1; Fig. 4 is a longitudinal section 6i' Fig; 3 is a sectional view taken on the Aline 3 is alongitudnalsectin of another modificationun themanner of connecting the tube to the handle-and to theshellor casing. Figs.

6 and 7 are side and edge views, respectively,

of the web whereonl the conductors are led through the main tube. 1 Fig. 8 is a side view of the .web, shwing. a different' manner ot' leading the conductingwires thereon. In said 'Figs.'67, and 8 the terminal block isalso shown. Fig. 9 is a side view of a moditied form of-web. Fig. .'IO is a perspective view of the preferrediorm' of bindingpost employed in connection with the terminal block. Figs. 11,12, 13, and 14:A are sectional views taken, respectively, onthe lines'll 11, 12 1,2,

13 13, and-i4 14, Fig. 8. Fig; '15 is' 'a fragmeritary detail vicw,.dra.wn' to anin'creased scale, illustrating the preferred manner of Joining the conductors c' and'e.

Similar letters refer to similar parts tliroughout the several views.

The inner tube a consists, preferably, ot'a single piece, or at least pieces brazed or other-Y wise permanently secured together so as to be virtually of a single piece, and said tube may be of uniform cross-section, as'shown in the main iigures of the drawings, or mayhave different cross-sections at' different points, as` illustrated in Fig. 4. l

Upon" tube (zare the various holding devices, wh ich may be considerably modilied,but which are here Yillustrated irl their preferred forms. At the forward extremity of the* tube is formed theannular flange af, which has an exf terior bevel surface c and an interior bevel surface a for the purposes hereingfter mentioned,. Said tube alsohas formed thereon in its preferred form the 'threaded collars af and c5, although said collars may, if desirable, be contiguous and unified, as shown in 'l Fig. 5.

,Inside of the tube la, at a convenient distance from the forward extremity thereof, is

formed an interior thread a for receiving the threaded inner extremity of the copper tip b.

An mperfora-tediaphragm'dis formed a'cros's tube a for the purpose of hermeti'cally sealing said tube ata point within the inner extremity of the tip 1). Said tip has an .annular bevel or shoulder Il', which is formed in such manner that when said tip b is screwed tightly down .into the threaded portion a. said shoulder bf will make air-tight contact with the bevel as; formed at'the mouth of tube a.

It will be understood that when copper is..

heated in the presencefof air it 'gradually has formed thereon a scaleof copper oxid', which is practicallya heat-insulator instead of aheatconductor." This is detrimental to the eiii:v ciency of the devicc'and can .be avoided only by preventing' theaccess of oxygen. l/Vith our construction when the tip b is screwed down tight the shoulder t hermetically seals the'mo'uth of the tube a and prevents the entrance of air from that direction, while the diaphragm alprevents the'access of air from the opposite direction'.

Upon the outside of the tube a, upon .the forward portion thereof, 'isfa winding of a I conductorhavinghigh resistance, so that heat will he generated when an electric current 'passes through it; Said winding is of course insulated by athin layerof mica'or other ma terial from tube t and constitutes one of the important features-y of this invention. The conductor c' of which the winding is composed. is wound. double, so thata complete'circuit from the positive to the negative terminal of the winding may .lie in a single layer, as best A other insulator d, around which the loop passes and over -which the adjacent turn's of the conductor pass to thereby firmly hold said strip in position. It will be seen that by this construction the conductor may be led from the near to theforward extremity of the winding and return in a single layer, thusobviating the necessity of laying asheet of mica or other insulator above the inleading spiral in order to bring the two ends of the conductor o ut at the same place. f f The purpose of the winding c isof course to transfer heat to the tip 6, andan advantge in` having the conductor all in the same layer is that it eliminates the necessity for an extra layer of insulation, which insulation would. reduce the heating effect upon tube a and tip of any wires outside of such extra layer.

Another ad vantage is that the two spirals may.

be wound on simultaneously, thus reducing the amount of` time required for the process.

In the preferred form the spirals constituting the winding c are n ot exactly parallel, but gradually and uniformly increase their distance apart as they get farther away from the securing-strip d. The purpose for this will be evident when itis considered that the potential difference Vbetween two adjacent spirals is substantially zero at loop c2 and is greatest at the supply-terminals. ency for a short circuit between any two adjacent turns decreases in the same ratio as the potential dilerencedecreases. The less the potential difference the less is the amount of space required between the turns for insulavuol AVAILABLE COP\ 'rectas l tion, and advantage is taken'of tliis'fact to de.

crease fthe space as the necessity for it is dcthat the turns are closest together at the forgreatest number of turns,` and consequently the greatest proportion of heat., will be close to the tip ZJ, the heat being thus applied in a most eliicient manner.

70. length of tube.- By so arranging the coil c -ward end of thetube a 'it follows that the' rfhe rear extremities of the heating-cond uctor c are electrically connected to the forward extremities of the' supply-conductors e, which lie chiefiy withinfsaid, tube, as will be hefeinafter mentioned.

The winding ois protected by being inclosed within the shell or casing f, which is beveled at its forward extremity to iitagainst the bevf eledsurface a2 at the forward extremity of tube a. Said casing bears at its' rear extremity upon the collar af and is held tightly against surface a2 by means of th'e jam-nutf', which screws onto the threaded portion of collar aL and abuts against the rear extremity of said casing.

It is desirable to prevent the turning of casing f, and this is conveniently accomplished by providing a longitudinal slot or recess a for receiving the indentation f, formed in said casing.

The su pply-conductors e, before mentioned,

lead backward within tube a to the bindingposts g g, which in the present instance are mounted in the terminal block /t and will be hereinafter referred to.

In order to insulate the supply-conductors e from each other and from tube a, a web i,

" of mica or other insulating material, is placed within the tube andforms a support for said conductors. The web may beheld fast in the. tube in any suitable manner, preferl ably by being made of a width almost equal to the inner diameter of said tube. The conductors may be strung along 'said web in different ways, the preferred methods .being shown in Figs. 6, 7, and 8, where the web has a series of perforationsv t" i occurring in pairs at short intervals and the conductors being 'threaded through them from one .surface of the web to the other. Thebest arrangement is shown in Figs. 6 and 7, where the conductors progress zigzag. across and along the web, always lying upon opposite surfaces thereof. The conductors may, however, lie parallel, as shown in Fig. 8.

It is possible to notch the web, as shown in Fig. 9, and lead the conductors e from one edge of the web to the other; but this is less desirable, asthe web is necessarily weaker, the

ITO

notches lhaving to be of considerabledepth to enable the conductors to-be kept atasafe d istance from the inclosing tube a.. It is obvious that the method of mounting held in tube a' byanysuitable meansf-as, for

convenience in .assembling a portion ofthe terminal block extends beyond the rear extremity of tube a." InJthe preferred form said bindingposts g cnsist-.of interiol'ynarylamp-cord'.

threaded sleeves and arelet into the terminal block in the manner asbestsbown in Fig. 13.V

Said posts are.electrieally connected 'to th'e conductorse and are adapted to receive the binding-screws g' formaking electrical contact with the supply-conductorsj. Said sp pply-conductors'mayy well consist of the ordi- The bindingposts 4g are arranged 'in tandem I n pon the terminal blockvwith theirheads opening-upon opposite sides thereof.' They are. .preferably securedby expanding orriveting over-their innerextremity, so as to engage'- 'the 'terminal block, as best shown in Fig. 1.3.A

The purpose ofthis construction ofthe bloc and binding-posts: is to'obtain-compactness, the whole being small enu'gh to be completely inclosed within. the bore.of the handle-lc.'

Near the' rear ejctremity of, the terminal block is an apcrtu rc It', through which the supply-conductors j are each led to the opposite side of the block, as best. shownin Fig. i.'

Th is crossing ofthe insulated conductors j is not csscntiahrbut is advantageous 'in that it` relieves the binding-screws` g'- of strain -in case j an accidental strain is put upon said supply.- conducto'rs .wliichlead from tliejextcrior of the device. Thefliandle l); above mentioned. consists,

preferably. of wood or similar non-conducting material 'and is bored longitudinally. forreceiving the terminal block le, and the rear portion of tube a.. -Said handle' incloses a sufhcient portion of tube a to afford a substantial bearingthereon. Said handle'is' provided vat its forward 'extremity with'a fer-rule m,

prcferablyof metal and -secured'by .means-of thc rivets 'm' or other' suitable devices. a In the preferred-construction the ferrnle -is inte-- 'rior-ly threaded, so as to screw onto the threaded collar 4?,. formed upon tube 0. In` order" that the ferrulc and handle may bc locked upon tubera, a shoulder 1w is formed upon thecol'- lar a." the ferrule may be screwed.

ln the preferred constructioh'the collars a "'are placed jat a slight 'distance apart, the.

purpose being to pern'iit-dissipation of heat back of the collar a, so that thehandle lr may remain perfectlycool.V Itis not necessary, however` that said collars be placed at a di's and thus affords a stoplagainst which.

DEO! HVHILHDLC UUI".

2, with the exception that the collar a takes the place ot' the twocollars a* a5, and the fer- 7o rule m and nutf' are both screwed upon the single collar a. In this arrangement the nut f'. performs thefunction of thefshoulderc in addition to its function of retaining the cas- 'ns'f-- 'L 75 It will be noted that the handle/l: is formed of a single piece, and this is rendered. possiv 'ble because of the compact construction of the terminal block-lt andthe manner of fastening the .conductors j to the binding-posts g.

- When the tool is being assembled, the webrf, .with theconductorsc thereon, is inserted in'to tube a, together with the terminal block t.

4The forward extremities of the conductors eV 'forward 'overthe rear extremity of the tube crl 'and is screwed down into position. thereon.

In case an extra-large'copper tip b2 is re- -quired. as shown in Fig. 4r, tube A increases loo its diameter at the point In this construction, as. before, the' diaphragm A.2 will he` formed 'within tube a for sealing the same, and the casingF will be o'a correspondingly greater diameter.

What we claim as new., anddesire to secure by Letters Patent, is r 1. In an elect-richeating device', a heatingcoil wu'nd in a double spiral and having its 'point more remote from'theioop.'for the purn pose of reducing thedangerlof short-ein" 2. 1n an electric heati'ng'device, a heating- 'coil wound in a double cylindrical spiral back- 1 i 5 ward roma loop therein` the distance between the turns gradually'increasing toward the terminals ofthe coil. l' '3.:1n an electric heating device. a metallic Aheating-tip and aresistaucecoil for heating the x 2o same, said coil being wound in double cylindricalspiralfrom a return-loop therein and, said'coil having its turns clo'ser together near the said loop than at a point more remote therefrom for the purpose described.

4. 1n an electric heating device, a metallic' heating-tip; 4a resistance-coil fon'heating the same, said coil being wound' in double cylin. drical spiral from'a retinal-loop.J therein; and

means at said loop for maintaining the same x3:

turns closer togethernear its loop-than ata um nation ofa heating-coil; a central bodyaround f a strip ofinsulating*materialor holding --the4 coil at the loop tberein," the turns o'f the. coil d adjacent to theloop passing .overfsaid strip.

in fixed-relationship with the remaining parts of the coil.I -said coil having itsturns closer together at said loop' than at the' parts more remote therefrom for the purpose of reducing the danger ofshort-circuiting, the-loop part of said coil lying nearest to the operative por-'- tionof said tip. 5. In an elebtric'lieating device. a heatingcoil, Va-'central body around which' the. coil is Wound'in double spiral, and a strip for hold.

ing thecoil at the loopedextremity thereof,

said strip being held in'v position upon the cen-- trallioody by means of -the'turns'ot'the coil itse. .-.a '6. In an electric heatingdevice,'the'conbi-- which. the coiljs wound. in 'double'. spiral;l and for iirmlyretaining the same in position. u'pon the said central bo'dy.-

" 7. In an electric heatingdevicathehcombi'e nation of a heating-coil; a centralbody around which the coil' is wound in double spirala-nd a strip of insulating material for holding the coil t'the loopfthereinithe turns of the coil adjacent to the loop Ipassin, 1,f oversaid strip for [irrnlyretainingthe same in position upon said centralbody, .and the distance' between .the turns of the coil becoming greater as the distancefrom theloop increases.

8. In'an electric heating dev ice, the combi- -nation of a: tube, an insulating vieb'th'eren .and an .electric conductormounted web out of contact with said tube.

9. In an electric heating device, the combination of a tube, a web'ofjnsulating material Ain said tube-having. a width approximatelyupon said equal to the inside diameter thereof; and an 'electric conductor mounted upon said web'and passing from one surface thereof to the other f at suitableintervalsto thereby remain out' of contact with said tube.

10. In an electric beating device, the combination of atube; 'aweb of insulating mate? rial extending approximately along the center thereof,sa1d1web having perfoations at suitable intervals therein; and a conductor. threaded through said apertures 'so as topass from' posite s nrfaces'of the web at. any given point.

therein whereby said conductors are kept out of'contact with each other.. A

v 12;: In an electric heating device, the cornbination of a metallic tipfor heating the .oh-

sEsT AVAILABLE com tenses ject to be heated, said ltipi havinganA annular beveled shcuiderlthereon-between its ends;

ymeans forfheatiug'said tip; a tube'for su pp orting, 'said tip; and an' imperforate diaphragm' within said tube' between the; ends'thereof,

said tube havihg'a beveledsurface at its mouth whereontothe Vbeveled shoulder on said tip may? be .wedged for A'sealing said tube.; l

13. Infan electric heating'dcvice, `the com'- bination of ametallic tip for heating 4the objectto be heated,'said tip having an'annular means 'for heating'said tip; a tube for supportl ing said tip,- an imperforate diaphragm'within said tube between the ends thereof; said tube having a beveled surface. 'at its mouthtgand means for tightly forcing the beveled-shoulder of said-tip down onto the beveled surface of said tube for sealing the mouthrthereof.

:. 14.111 anelectric heating device;v the com:

Ibination of a heating-tube having an annu la.'

' .beveled shoulder thereong. meansior heating said tube; and a casi-ng for inclosing said heat;

'ing'meana said casing having'a beveled surbeveledshoulder thereon between its ends;

face whereby Js'ad casing may be wedgedhgo against the beveled shoulder on said tube.

'15. In an electric heating-device, the coin# bination of a heating-tube? having an annular `'beveled shoulder thereon; a heat-generating'- resistance medium -upon said tube; a casingfor inclosing said resistance medium, said cas .lng having a. bevel at one end ior'contactmg the' shoulder on said tube; and means'at the rear end of-said casing for forcing and holding it against the said 'shoulder on said tube.

16.1 Inan electric heating device, the combination of an electric heat-generator; a terminal' block; conductors leading from said block to said heat-generator; and bindingposts on said bloclc makingrcontact with said conductors and .adapted tolbe connected to suitable supply-wires, said binding-posts being arranged in tandem upon said terminal block for thepurpose described. 17: In an electric heating-device, the combination of a heat-generator; a tube support ing the same; aterminal block secured 'to said IIO tube at the rear, extremity thereof; conductors leading from .said heat-generatorto the terminal block; and bindingposts on fsaid 'block making electrical contact with said conductors and adapted to be connected to suitable supply-wires, said binding-posts'being arranged in tandem upon said terminal block; for the purpose described.

. 18. [n-an electric heater, the combination of a tube; a' resistance medium mounted on said to said 'terminal block and fastened-thereto;

block to said resistancemedium, saidV termi- .tube vfor generating heat; a terminal block supported cou said tube'; conductors leading' other conductors leading from said terminal nal block and all of said conductors being supported-'on said tube; and. longitudinallybored handle rigidljsecured to said tube', said handle being adapted to circumferentially inclose said terminal block and a portion of said conductors and being independentof said terminal 'block and conductors.

19. Inan electric heater,the combination of a tube; a resistance medium mounted on said tube for generating heat; a terminal block` t va single one-piece tube constituting the foutdational structure of the device, aresistance medium 'wound upon one en'd thereof, for generating heat, conductors leading into the other end of said tuber for supplying electric current to said .resistance medium; and a longitudinally-bored, one-piece handle fitting over the rearend of said tube and adapted tobe slid thereontofrom the rear thereof.

21. In an electric,` heater, thecombination of a tube constituting theY foundational structure 5 said tip and coil and handle being all mount-,

of the device; a resistance medium near one end thereof' for generating heat; alterminal block lying partially within said tube and projectingout of the rear end thereof.; supplyconductors leading from the source of energy tosaid terminal block; other conductors leads.

' ing from said terminal block to said heatgeneratingmedium; and alongitudinally-bored, one-piece handle fitting over the rear end f said tube and adapted to be slid thereontofrom the rear thereof, said handle thereby inclosing said terminal block.

22. In au electric heater, the combination of a tube; a metallic tip rigidly secured at they forward end thereof; a heating-coil upon said tube adjacent to said tip; and a handle rigidly secured to said tube. at the rear end thereof,

BEST AVAILABLE cowL ed on the same piece whereby the device is rigid from end to end.

23. In an electric heater, the combination of a tube having perforations in the side thereof; a metallic tip at the forward end of said tube; a beat-generating resistance medium located upon the outside of said coil'adjacent to said tip; conductors leading within said tube from the rear end thereof and passing outward through the said perforations therein-to join said heat-generating medium; and a web of insulating material located within said tube and supporting said conductors.

21h Inan electric heater, the combination of a tube havingperforations in the side thereof; a metallic tip at the forward end ot' said tube; a heat-generating resistance medium located upon the outside of said coil adjacent to said' tip; conductors leading within said tube from the rear end thereof and passing outward through the 'said perforations therein to join said heatgenerating medium; and a web of Vinsulating material vlocated within said tube and supporting said conductors to insulate the same, said web having suliicient stiffness to carry forward the free forward ends of the said conductors during assemblage, whereby the said ends may be threaded out through `the apertures in said tube to bejoined with said heat-generating medium.

' 25. In an electric heater, the combination of a tube,'a handle, screwing onto the rear end thereof; ametallic tip supported by said tube at the front end thereof; a heat-generating medium located on the outside of said tube adjacent to said tip; a casing outside of said heat-generating' medium slidable lengthwise of saidtube; a rigid, longitudinally-slotted collar upon said tube, and an inward projection'upon said casing. for entering the slot in said collar whereby the casing may be moved longitudinally but is prevented from turning,

'said casing thereby 'affording means whereby the device may be .gripped in screwing the handle on or-otf.

-LOUIS P. BROWN.

FRANK J. HOLMES. Witnesses:

Howam) M( Cox.,

ELEoNoBE J.- MARLIN.. 

